Smart sunshade for a vehicle window

ABSTRACT

A system for reducing sunlight shining into a vehicle includes a window having an array of liquid crystals switchable between a transparent state and a shaded state. The system also includes an eye position sensor for detecting a location of eyes of a driver and an inertial measurement unit (IMU) for detecting a current heading of the vehicle. The system also includes an electronic control unit (ECU) that may determine a current location of the sun relative to the vehicle based on the current heading of the vehicle and a current time of day. The ECU may also select an area of the window to be shaded in order to reduce an amount of sunlight reaching the eyes of the driver and control liquid crystals within the selected area of the window to switch from the transparent state to the shaded state.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.15/055,364 entitled “Smart Sunshade for a Vehicle Window,” filed on Feb.26, 2016, now U.S. Pat. No. 9,702,183, which is hereby incorporated byreference herein in its entirety.

BACKGROUND Field

The present disclosure relates to systems and methods for automaticshading of a portion of a vehicle window and, more particularly, fordetermining where to shade the window to prevent, or reduce an amountof, sunlight from reaching the eyes of the driver and for controllingliquid crystals of the window to provide the shade.

Description of the Related Art

Most conventional vehicles include a sun visor for a driver and a sunvisor for a passenger. These sun visors are attached to an interior ofthe vehicle cabin above the windshield. A typical sun visor can rotateto a position in which it covers a portion of the windshield or a driveror passenger window. Conventional sun visors have a length ofapproximately 6 inches that may cover a portion of a windshield orwindow, such as the top one third to one quarter of the windshield, whenfully extended. Conventional sun visors are opaque and have notransparency.

In some locations, such as on flat areas of land in the western UnitedStates, the shade afforded by sun visors may provide insufficient shadeor blocking of the sun. This may be especially true for a period of timeafter dawn and before dusk. During these times direct sunlight can shinethrough the windshield at a location below the reach of the sun visorsand shine in the driver's and front passenger's eyes. This directsunlight is not only unpleasant and hazardous to the health of thedriver and passenger (as it can cause eye damage) but it also createsdangerous driving conditions. For example, a driver may not be capableof seeing the current conditions of the road if the sun is shiningdirectly into his or her eyes.

Thus, there is a need for systems and methods for providing shade on avehicle window to reduce an amount of direct sunlight shining into adriver's or passenger's eyes.

SUMMARY

Described herein is a system for reducing sunlight shining into avehicle. The system includes a window having an array of liquid crystalsthat can each be switched between a transparent state and a shadedstate. Less light may pass through the liquid crystals when they are inthe shaded state than when they are in the transparent state. The systemalso includes an eye position sensor for detecting a location of theeyes of a driver. The system also includes an inertial measurement unit(IMU) for detecting a current heading of the vehicle. The system alsoincludes an electronic control unit (ECU) coupled to the array of liquidcrystals, the eye position sensor and the IMU. The ECU may determine acurrent location of the sun relative to the vehicle based on the currentheading of the vehicle and a current time of day. The ECU may alsoselect an area of the window to be shaded in order to reduce an amountof sunlight reaching the eyes of the driver based on the location of theeyes of the driver and the current location of the sun relative to thevehicle. The ECU may also control liquid crystals within the selectedarea of the window to switch from the transparent state to the shadedstate.

Also described is a system for reducing sunlight shining into a vehicle.The vehicle includes a window having an array of liquid crystals thatcan each be switched between a transparent state and a shaded state inwhich less light can pass therethrough. The system also includes adriver-facing camera configured to detect a current location of exposedskin of a driver. The system also includes a sun position sensorconfigured to detect a current location of the sun relative to thevehicle. The vehicle also includes an ECU coupled to the array of liquidcrystals, the driver-facing camera and the sun position sensor. The ECUmay select at least one area of the window to be shaded in order toreduce an amount of sunlight reaching the exposed skin of the driverbased on the current location of the exposed skin and the detectedcurrent location of the sun relative to the vehicle. The ECU may alsocontrol liquid crystals within the at least one selected area of thewindow to switch from the transparent state to the shaded state.

Also described is a method for reducing sunlight shining into a vehicle.The method includes detecting, by an eye position sensor, a location ofthe eyes of a driver. The method also includes detecting, by an IMU, acurrent heading of the vehicle. The method also includes determining, byan ECU, a current location of the sun relative to the vehicle based onthe current heading of the vehicle and a current time of day. The methodalso includes selecting, by the ECU, an area of a window of the vehicleto be shaded in order to reduce an amount of sunlight reaching the eyesof the driver based on the location of the eyes of the driver and thecurrent location of the sun relative to the vehicle. The method alsoincludes controlling, by the ECU, liquid crystals within the selectedarea of the window to switch from a transparent state to a shaded statein which less light can pass therethrough.

BRIEF DESCRIPTION OF THE DRAWINGS

The features, obstacles, and advantages of the present invention willbecome more apparent from the detailed description set forth below whentaken in conjunction with the drawings, wherein:

FIG. 1 is a block diagram of a vehicle having a window with liquidcrystals for providing shade between a driver's eyes and the sunaccording to an embodiment of the present invention;

FIG. 2 is an exemplary portion of a sun movement chart showing variouspositions of the sun in the sky based on a time of day according to anembodiment of the present invention;

FIG. 3 is a drawing of a cabin of the vehicle of FIG. 1 with awindshield having liquid crystals and various sensors for detecting datacorresponding to the location of the sun and the eyes of the driveraccording to an embodiment of the present invention;

FIG. 4A is a drawing of the cabin of FIG. 3 showing the windshield ofFIG. 3 in which at least some liquid crystals in an area between the sunand the driver's eyes are in a shaded state according to an embodimentof the present invention;

FIG. 4B is a drawing of some liquid crystals of the area of FIG. 4A withsome liquid crystals being in the shaded state and some of the liquidcrystals being in a transparent state according to an embodiment of thepresent invention;

FIG. 5 is another drawing of the cabin of FIG. 3 with a first area ofthe windshield between the sun and the driver's eyes that has a darkshading and a second area extending outward from the first area that haslighter shading according to an embodiment of the present invention;

FIG. 6 is a flowchart illustrating a method for providing shade on avehicle window using liquid crystals between the sun and driver's eyesaccording to an embodiment of the present invention;

FIG. 7 is a drawing showing a top-down view of the sun and the vehicleof FIG. 1 on a road along with axes for illustrating a heading of thevehicle according to an embodiment of the present invention;

FIG. 8 is a drawing showing a side view of the vehicle of FIG. 1 on aroad and the sun along with axes for illustrating a pitch of the vehicleaccording to an embodiment of the present invention;

FIG. 9A is a drawing of a driver's face in a cabin of the vehicle ofFIG. 1 along with an area of shade on the driver's face according to anembodiment of the present invention;

FIG. 9B is a drawing of the driver's face of FIG. 9A with the area ofshade moved to shade both of the driver's eyes according to anembodiment of the present invention; and

FIG. 10 is a flowchart illustrating a method for determining a locationof the sun relative to a vehicle based on machine learning according toan embodiment of the present invention.

DETAILED DESCRIPTION

Described herein are systems and methods for providing shade to a driveror a passenger of a vehicle using liquid crystals of a window. Thesystems and methods provide several benefits and advantages such asproviding shade between the driver's eyes and the sun without anyactions required by the driver. The systems and methods provide furtherbenefits and advantages such as the ability to verify whether the shadedarea of the window is actually providing shade where desired and theability to periodically or continuously move the shaded area of thewindshield to realign the shade between the driver's eyes and the sun.This provides benefits and advantages such as increased driver comfortbecause direct sunlight will not be shining in his or her eyes andincreased personal and vehicular safety for the same reasons. Thesystems and methods provide further benefits and advantages such as theability for the driver to see the road and/or environment through theshaded area of the window, further increasing vehicular safety.

An exemplary system includes at least one window having liquid crystals.The system also includes an eye position sensor for detecting thecurrent location of the driver's eyes and an inertial measurement unit(IMU) for detecting a current heading and pitch of the vehicle. Thesystem also includes an electronic control unit (ECU). The ECU candetermine a current location of the sun relative to the vehicle based onthe current heading of the vehicle and a current time of day. Forexample, the ECU may compare the current time of day to a sun movementchart to determine a location of the sun in the sky and may compare theheading and pitch of the vehicle to the location of the sun in the sky.The ECU may also select an area of the windshield that is directlybetween the driver's eyes and the sun based on the detected location ofthe driver's eyes and determined location of the sun. The ECU maycontrol liquid crystals within the area to switch to a shaded state toreduce an amount of sunlight that reaches the driver's eyes.

Turning to FIG. 1, a vehicle 100 includes features for shading windowsto reduce an amount of sunlight from reaching a driver's eyes. Thevehicle 100 may include an ECU 102, a memory 104, a network accessdevice 106, a global positioning system (GPS) unit 108, an IMU 110 andan input device 112. The vehicle 100 may also include multiple sensorssuch as a driver eye position sensor 114, a forward-facing camera 116, asunlight sensor 118 and a passenger eye position sensor 120.

The ECU 102 can include one or more processors or controllers which maybe specifically designed for automotive systems. The functions of theECU 102 can be implemented in a single ECU or in multiple ECUs. The ECU102 may receive data from components of the vehicle 100, may makedeterminations based on the received data and may control the operationof components based on the determinations and received data.

The memory 104 may include any non-transitory memory known in the art.The memory 104 may store machine-readable instructions usable by the ECU102 and may store any other data as requested by the ECU 102.

In some embodiments the memory may store a sun location chart. The sunlocation chart may include data such as locations of the sun in the skyfor various dates, times of day and locations. For example, the sunlocation chart may provide the direction and vertical position of thesun for a given location, date and time of day.

Referring briefly to FIG. 2, an exemplary sun location chart 200provides the direction and vertical position of the sun relative to thehorizon for a particular location, date and time of day. For example,the sun location chart 200 shown in FIG. 2 may provide sun location datafor zip code 92626 on Feb. 10, 2016 between 12 o'clock pm (12 pm) and 1pm. The sun location chart may include data based on the currentlocation and direction of travel of the vehicle and the particular dateand time of day. A sun location chart may include data similar to thedata shown in FIG. 2 and/or may include data for multiple locations,multiple dates and more times of day. For example, a sun location chartmay be provided having sun location data corresponding to each day ofthe year and each time of day for each location in the United States.

The direction provided in the sun location data corresponds to adirection along the North, South, East and West axes. For example, at12:00 pm the direction of the sun is 160 degrees which corresponds to aSouth-Southeast direction. The vertical position relative to the horizoncorresponds to how high the sun is above the horizon. For example, at12:00 pm, the vertical position of the sun is 65 degrees, whichindicates that the sun is positioned 65 degrees above the horizon.

Returning to FIG. 1, the network access device 106 may include anydevice capable of communicating with an external device or network. Forexample, the network access device 106 may communicate with the cloud122 via 3G protocols, 4G protocols, 802.11 (Wi-Fi) protocols or thelike.

In some embodiments the network access device 106 may also or insteadinclude an input/output (I/O) port. In that regard, the network accessdevice 106 may connect to other devices via a wired or wirelessinterface. For example, the network access device 106 may be a USB port,a Wi-Fi port, a Bluetooth port, a Dedicated Short-Range Communications(DSRC, usable in vehicle-to-infrastructure or vehicle-to-vehiclecommunications) port or the like. The network access device 106 maytransmit data to and receive data from an external device such as amobile phone (not shown) or telematics device which may in turncommunicate with the cloud 122 or other vehicles (not shown). In thatregard, the ECU 102 can communicate with the cloud 122 via the networkaccess device 106 and the mobile phone.

In some embodiments the cloud 122 may include a sun location map. Inthat regard, the ECU 102 may transmit a current location, time of dayand/or date to the cloud 122 and may receive sun location datacorresponding to a direction and vertical position of the sun from thecloud 122 in response.

The GPS unit 108 may include one or more GPS receivers capable ofreceiving location data corresponding to a current location of thevehicle 100. In that regard, the ECU 102 can determine a currentlocation of the vehicle 100 based on data from the GPS unit 108.

The IMU 110 may include any sensor or sensors capable of detectinginertial movement of the vehicle 100. For example, the IMU 110 mayinclude a gyroscope, an accelerometer, a magnetometer or the like. TheIMU 110 may detect data corresponding to an acceleration of the vehicle100 in one or more directions. For example, the IMU 110 may be a 2 or 3axis accelerometer capable of detecting acceleration along 2 or 3 axes.The IMU 110 may detect data corresponding to a heading of the vehicle100 (i.e., in the North, South, East and/or West directions) along witha pitch of the vehicle 100 relative to the horizon (i.e., an angle ofthe vehicle relative to the horizon).

The input device 112 may include any input device capable of receivinguser input. For example, the input device 112 may include a button, aknob, a dial, a touchscreen, a touchpad, a microphone or the like. Theinput device 112 may be coupled to the ECU 102 such that the ECU 102 canreceive user input. The input device 112 may receive user inputindicating, for example, whether the user would like for an automaticsunshade feature of the vehicle 100 to be turned on or off.

The driver eye position sensor 114 may include any sensor capable ofdetecting data corresponding to a location of the eyes of the driver.For example, the driver eye position sensor 114 may include adriver-facing camera that detects image data corresponding to an area ofa cabin of the vehicle 100 in which a driver's head is likely to bepositioned. The ECU 102 can receive the image data and determine thelocation of the driver's eyes within the vehicle 100 based on thereceived image data.

In some embodiments, the driver eye position sensor 114 may include morethan one driver-facing camera or other driver eye position sensor. Insome embodiments, the one or more driver eye position sensor 114 maydetect data corresponding to a larger portion of the driver such as thedriver's head. The ECU 102 may determine a location of the whole head ofthe driver based on the detected data from the driver eye positionsensor 114. In some embodiments, the ECU 102 may determine a size of thedriver's head or face and determine the location of the entire head orface of the driver based on the size of the driver's head and thedetermined location of the driver's eyes.

In some embodiments, the driver eye position sensor 114 may detect datacorresponding to the entire body of the driver. The ECU 102 may use thisdata to determine the location of the driver's entire body. The ECU 102can differentiate the detected colors or tones and determine locationsin which the driver's skin is exposed to sunlight.

The driver eye position sensor 114 may also or instead be a pressuresensor positioned in a headrest of a driver seat of the vehicle 100. Inthat regard, the ECU 102 may determine or estimate a location of adriver's head based on the detected pressure in the headrest. The ECU102 may also estimate the location of the driver's eyes based on thelocation of the driver's head and the detected pressure. For example,the pressure sensor may detect the most pressure in the middle of theheadrest, indicating that the center of the driver's head is in themiddle of the headrest. The pressure sensor may also detect morepressure to the left of the middle than to the right of the middle,indicating that the driver is looking left and thus his eyes will beleft of the middle of his head.

The forward-facing camera 116 may detect data corresponding to an areaoutside of the vehicle 100. For example, the forward-facing camera 116may detect data in front of the vehicle 100, to either side of thevehicle 100 and/or behind the vehicle 100. In that regard, theforward-facing camera 116 may include multiple cameras positioned aboutthe vehicle 100.

The forward-facing camera 116 may detect a location of the sun. Becausethe forward-facing camera 116 is facing a fixed direction relative tothe vehicle 100, the ECU 102 may use the detected location of the sun todetermine the location of the sun relative to the vehicle. For example,the ECU 102 may determine that the sun is directly ahead and 45 degreesabove a current heading and pitch of the vehicle 100 based on the imagedata detected by the forward-facing camera 116.

The sunlight sensor 118 may include any sensor capable of determiningwhether the sun is shining (such as whether it is nighttime, whether thesun is behind clouds or the like) and/or determining whether sunlight isreaching the interior of the vehicle's cabin.

The passenger eye position sensor 120 may include similar features asthe driver eye position sensor 114.

Turning now to FIGS. 1 and 3, a view of a cabin 300 of the vehicle 100is shown. The driver eye position sensor 114 includes a driver-facingcamera 302 and the passenger eye position sensor 120 includes apassenger-facing camera 304. Furthermore, the sunlight sensor 118includes a driver-side sunlight sensor 306 and a passenger-side sunlightsensor 308. The driver-side sunlight sensor 306 may detect whethersunlight is shining into the driver side of the cabin 300 and thepassenger-side sunlight sensor 308 may determine whether sunlight isshining into the passenger side of the cabin 300.

The driver-facing camera 302 may be positioned on a steering wheel 310or elsewhere in the cabin 300. The driver-facing camera 302 should be ata position in which it can detect the location of the driver's eyes atmost or all reasonable driver positions. For example, the driver-facingcamera 302 should be able to detect the location of the driver's eyeswhen the driver leans or turns his head to the left or right.

The passenger-facing camera 304 may be positioned on a dashboard 312 orelsewhere in the cabin. Like the driver-facing camera 302, thepassenger-facing camera 304 should be able to detect the location of thepassenger's eyes when the passenger leans or turns his head left orright.

The driver-side sunlight sensor 306 and the passenger-side sunlightsensor 308 may be positioned on a rear-view mirror 314 or elsewhere inthe cabin. The driver-side sunlight sensor 306 should be positioned suchthat it can detect whether sunlight is entering the driver side of thecabin. The passenger-side sunlight sensor 308 should be positioned suchthat it can detect whether sunlight is entering the passenger side ofthe cabin.

The vehicle 100 includes multiple windows including a windshield 316, adriver window 318 and a passenger window 320. The vehicle 100 may alsoinclude a rear window (not shown) and may potentially include additionalwindows corresponding to a back seat.

One or more of the windows of the vehicle 100 may include an array ofliquid crystals or other material or technology that can beelectronically controlled to switch states between a transparent state(in which all light may pass therethrough) and a shaded state (in whichsome or no light may pass therethrough). The shaded state provided avalue or a range of tinting, blocking and/or filtering of the sun'srays. For example, the tinting can be 25 percent blocking of the sunlight. Also, for example, the range can be between 10 percent tint to 50percent tint. The shaded state may provide protection against harmful ordamaging rays such as ultraviolet (UV) rays. The shaded state mayinclude polarization similar to a polarizing filter or a polarizingglass.

The ECU 102 may be coupled to the array of liquid crystals and maycontrol the liquid crystals individually to cause some of them to be inthe transparent state and some of them to be in the shaded state. Insome embodiments, the liquid crystals may be positioned on an entirewindow or only a portion of the window. For example, liquid crystals maybe positioned on the top two thirds of the windshield 316 but not on thebottom third or not positioned on the extreme left and right edges ofthe windshield 316. In one embodiment, the liquid crystals may includetinting and/or polarization to protect against harmful or damaging rayssuch as ultraviolet (UV) rays.

The ECU 102 may compare a detected location, date and time of day to thesun movement chart in the memory 104 to determine a current location ofthe sun 322. Alternatively, the ECU 102 may provide some of this memoryto a remote device in the cloud 122 and receive sun location data inreturn. The ECU 102 may compare the current location of the sun 322 tothe current heading and/or pitch of the vehicle 100 to determine thelocation of the sun 322 relative to the vehicle 100 (i.e., whether thesun is 5 degrees above the pitch of the vehicle, whether the sun 322 is10 degrees to the left of the heading of the vehicle or the like). TheECU 102 may then verify the location of the sun 322 relative to thevehicle 100 by comparing the determined location of the sun 322 relativeto the vehicle to the location of the sun 322 relative to the vehicle100 detected by the forward-facing camera 116.

The ECU 102 may compare the location of the sun 322 relative to thevehicle 100 to the location of the driver's eyes (and/or passenger'seyes) relative to the vehicle 100. The ECU 102 may determine a locationor area on the windshield 316 that is directly between the sun 322 andthe driver's eyes based on this comparison. The ECU 102 may then controlsome or all of the liquid crystals in the area between the sun 322 andthe driver's eyes to switch to the shaded state. This reduces an amountof sunlight that reaches the driver's eyes, providing shade to thedriver's eyes from the sun. Stated differently, this prevents direct(i.e., unshaded) sunlight from reaching the driver's eyes.

Turning now to FIGS. 1 and 4A, the ECU 102 has determined that an area400 of the windshield 316 is between the sun 322 and the driver's eyes.The ECU 102 has further controlled at least some liquid crystals in thewindshield 316 such that the area 400 is shaded.

Referring to FIGS. 4A and 4B, a portion 402 of the windshield 316 withinthe area 400 is shown. Within the portion 402 are multiple liquidcrystals 404. The liquid crystals 404 may be applied to the windshield316 in various manners. For example, the liquid crystals 404 may beprovided in sheet form and affixed to the glass of the windshield 316via a bonding process. Bonding of the sheet to the glass may occurbefore or after installation of the glass onto the vehicle 100. In someembodiments, the liquid crystals 404 may be inserted or coupled to theglass during manufacture of the windshield 316. For example, two sheetsof glass may be manufactured, the liquid crystals may be placed betweenthe two sheets of glass then the sheets of glass and/or liquid crystalsmay be coupled and/or bonded together to form the windshield 316.

At least some of the liquid crystals 404 in the area 400 are to beswitched to the shaded state in order to shade the driver's eyes fromthe sun. As shown in FIG. 4B, some of the liquid crystals 404 are in thetransparent state 406 and some of the liquid crystals 404 are in theshaded state 408. It may be undesirable for each of the liquid crystals404 in the area 400 to be in the shaded state as this may affect thedriver's visibility (i.e., the liquid crystals 404 may prevent thedriver from seeing through the area 400 of the windshield 316). However,because only some of the liquid crystals 404 are in the shaded state408, the driver has visibility through the area 400.

The ratio of shaded liquid crystals 408 to transparent liquid crystals406 may be predetermined based on a desired visibility and a desiredamount of shade. For example, if more shading of the sun is desired,more liquid crystals 404 may be in the shaded state 408 than if highervisibility is desired. In some embodiments, the driver may use the inputdevice 112 to select an amount of shade or visibility desired. The ECU102 of FIG. 1 will adjust the ratio of shaded liquid crystals 408 totransparent liquid crystals 406 based on this input.

In some embodiments, more than one amount of shading or visibility maybe provided. Turning to FIG. 5, an area 500 of the windshield 316 has afirst portion 502 having a first amount of shading and a second portion504 having a second amount of shading that is less than the first amountof shading. For example, the first portion 502 may be directly betweenthe sun 322 and the driver's eyes and the second portion 504 may extendaway from the first portion 502. The first portion 502 provides directshading for the driver's eyes and the second portion 504 provides shadefor the driver's eyes in case the driver quickly changes the position ofhis head. The second portion 504 further reduces an amount of indirectsunlight that may reach the driver's eyes.

Referring again to FIGS. 4A and 4B, in some embodiments, the liquidcrystals 404 may have a partially shaded state in which they arepartially transparent such that some, but not all, light may passtherethrough. In these embodiments, each of the liquid crystals 404 maybe partially shaded. In that regard, the driver may see through theshaded liquid crystals. In some embodiments, the liquid crystals 404 mayhave more than one shaded state. For example, the liquid crystals 404may have a partially shaded state and a fully shaded state in which nolight, or less light than the partially shaded state, may passtherethrough.

In some embodiments, some or all of the windows of the vehicle 100 mayinclude liquid crystals and be capable of providing shade. In someembodiments shade may be provided to any passenger of the vehicle in anylocation of the vehicle.

Turning now to FIG. 6, a method 600 for providing shade for a driver ofa vehicle is shown. The method 600 may be performed by components of avehicle such as the vehicle 100 of FIG. 1.

The method 600 begins at block 602 where an ECU may determine a currentlocation of the vehicle, a current date, a current time of day, acurrent heading of the vehicle and a current pitch of the vehicle. Thisdata may be determined based on data received from components such as aGPS unit, a clock, an IMU or the like.

Turning to FIG. 7, a top-down view of the vehicle 100 on a road 700 isshown along with axes showing the North, South, East, West, up and downdirections. Where used herein, a heading refers to a direction along theNorth, South, East, West plane, and combinations thereof. For example,the heading of the vehicle 100 may be referred to as 0 degrees becausethe vehicle 100 is heading directly north.

Turning to FIG. 8, a side view of the vehicle 100 on the road 700 isshown along with a horizontal axis and the up and down (vertical) axis.The horizontal axis corresponds to the North, South, East, West plane.As shown, the vehicle 100 is traveling upwards and is not parallel withthe horizontal axis. The pitch P of the vehicle 100 relative to thehorizon is shown as the difference between the horizontal direction andthe direction of travel of the vehicle along the up and down axis.

Returning to FIG. 6, in block 604, the ECU downloads or accesses a sunlocation chart that includes sun location data. The sun location chartmay be stored in a memory of the vehicle or may be stored in the cloud.If the sun location chart is stored in the cloud, the ECU may download aportion of, or the entire, sun location chart or may access a portionof, or the entire, sun location chart. The sun location chart may havesimilar data as the sun location chart 200 shown in FIG. 2.

In block 606, the ECU may determine a current location of the sunrelative to the vehicle. The ECU may determine the relative location ofthe sun based on the current location of the vehicle, the current timeof day, the current heading of the vehicle, the current pitch of thevehicle and the sun location data from the sun location chart. Thecurrent location of the sun may be provided as having a direction and anangle relative to the horizon. The ECU may determine the location of thesun relative to the vehicle by comparing the current location of the sunto the current heading of the vehicle and the current pitch of thevehicle.

For example and referring again to FIGS. 7 and 8, the vehicle 100 has acurrent heading of directly north, or 0 degrees, or 360 degrees. Thevehicle 100 has a current pitch P of about 25 degrees. The sun ispositioned in a northwest location in the sky such as, for example, 315degrees and is about 45 degrees above the horizon. The ECU may determinethat the current location of the sun 322 relative to the vehicle 100 is45 degrees to the left of the current heading of the vehicle 100 (360degrees minus 315 degrees) and 20 degrees above the current pitch of thevehicle 100 (45 degrees minus 25 degrees).

Returning to FIG. 6, after the ECU determines the current location ofthe sun relative to the vehicle, the ECU may determine a currentlocation of eyes of the driver. The ECU may determine the currentlocation of the eyes of the driver based on the detected image data froma driver-facing camera. The driver-facing camera may be at a fixedlocation within the vehicle. Thus, the ECU can determine the location ofthe driver's eyes relative to the vehicle due to the fixed nature of thedriver-facing camera.

In block 610, the ECU may detect the current location of the sunrelative to the vehicle using a forward-facing camera. Because theforward-facing camera is at a fixed location on or in to the vehicle,the ECU can determine the location of the sun relative to the vehiclebased on the image data from the forward-facing camera.

In block 612, the ECU may determine a location of the sun relative tothe eyes of the driver. Because the ECU is aware of the location of theeyes of the driver relative to the vehicle and aware of the location ofthe sun relative to the vehicle, the ECU can determine the location ofthe sun relative to the eyes of the driver. The ECU may determine thelocation of the sun relative to the eyes of the driver based on at leastone of the determined location of the sun relative to the vehicle or thedetected location of the sun relative to the vehicle.

In some embodiments, the ECU may first compare the determined locationof the sun relative to the vehicle and the detected location of the sunrelative to the vehicle. If the detected and determined locations of thesun relative to the vehicle are the same, the method 600 may proceedusing that value. However, if the values are different, the ECU mayselect one of the determined or the detected current location of the sunrelative to the vehicle and the method 600 may proceed with that value.In some embodiments, one of the detected or determined location of thesun relative to the vehicle may be given priority over the other.

In some embodiments, the ECU may determine which data is more likely tobe accurate. For example, the ECU may determine whether one or morecomponents is faulty and select the determined or the detected currentlocation of the sun relative to the vehicle based on the faultycomponent. For example, if the IMU is faulty, the determined location ofthe sun relative to the vehicle may be inaccurate because the detectedheading or pitch of the vehicle may be inaccurate. Thus, in thissituation, the ECU may proceed with the method 600 using the detectedcurrent location of the sun relative to the vehicle. As another example,if the ECU determines that the forward-facing camera is faulty, the ECUmay proceed with the method 600 using the determined current location ofthe sun relative to the vehicle.

In block 622 (discussed in further detail below), the ECU adjusts thelocation of the area of shade if direct sunlight reaches the eyes of thedriver. This may include selecting the other of the determined or detectcurrent location of the sun relative to the vehicle if the values didnot match in block 612.

After determining the location of the sun relative to the eyes of thedriver, the ECU may select or determine an area of one or more vehiclewindow to shade to reduce an amount of sunlight that reaches the eyes ofthe driver in block 614. The ECU may select the area to be directlybetween the eyes of the driver and the sun. In that regard, when thearea is shaded, direct sunlight is prevented from reaching the eyes ofthe driver. In some embodiments, the ECU may determine a point or anarea on the vehicle window that is between the eyes of the driver andthe sun. In that regard, the area will be selected based on the size,color and shape determined in block 616.

In block 616, the ECU may determine a size, color and shape of the area.For example, the ECU may determine the size, color, shape and shading ofthe area based on user input. In some embodiments, the user may be ableto select a desired amount of shade (i.e., corresponding to a ratio ofshaded to transparent liquid crystals in the area).

In some embodiments, the area is not customizable and is predeterminedby the ECU. For example, the area may be a shape having predetermineddimensions such as a circle having a 3 inch radius. For example, acenter of the circle may be positioned directly between the driver'seyes and the sun and the circle may extend for 3 inches in eachdirection. If a location on the windshield is not directly between thedriver's eyes and the sun then the area may still be present on thewindshield. For example, if the location directly between the driver'seyes and the sun is one inch above the top of the windshield, the areamay extend for 2 inches below the top of the windshield.

In block 618, the ECU may control some or all of the liquid crystalswithin the selected area to switch to the shaded state. Each of theliquid crystals may have one or more shaded states. For example, aliquid crystal may have a partially shaded state and a fully shadedstate. Furthermore, each liquid crystal may have multiple shaded statesthat correspond to different colors or darkness. For example, a liquidcrystal may have a red shaded state, a blue shaded state, a green shadedstate or the like. When the ECU controls the liquid crystals within thearea to switch to the shaded state, the ECU may control each of theliquid crystals to switch to the same shaded state or a different shadedstate. For example, the user may select for the area to resemble arainbow. In that regard, the ECU would control some of the liquidcrystals to be in the blue shaded state, some to be in the red shadedstate and the like.

In block 620, the ECU may determine the location of sunlight relative toeyes of the driver. The driver-facing camera may detect image datacorresponding to the driver's eyes and the location of the directsunlight. The ECU may determine the location of the sunlight relative tothe eyes of the driver based on the detected image data from thedriver-facing camera.

Turning briefly to FIG. 9A, exemplary image data detected by adriver-facing camera is shown. A driver 900 is in the cabin 300 of thevehicle 100. An area of the driver's face 906 including his right eye904 is shaded while direct sunlight is reaching the rest of the driver'sface including his left eye 902.

Returning to FIG. 6, in block 622, the ECU may adjust the location ofthe area if the direct sunlight is reaching one or both eyes of thedriver. The ECU may adjust the location of the area based on thedetected image data. In some embodiments, the ECU may perform some orall of the steps of the method 600 of FIG. 6 in order to change thelocation of the area.

In some embodiments, the ECU may adjust the area of to be shaded basedon the detected image data from the driver-facing camera. For exampleand referring to FIGS. 9A and 9B, the ECU may determine that the area ofshade should be moved from its location in FIG. 9A to provide shade at anew area of the driver's face 908 that is to the left of the originalshaded area of the driver's face 906.

Thus and with brief reference to FIG. 6, the ECU may control thewindshield of the vehicle to continuously provide shade between the sunand the driver's eyes using the method 600. In some embodiments, the ECUmay perform the method 600 to provide shade for a driver's face, head,entire body or any exposed skin. In that regard, the method 600 may beperformed using the same blocks with the driver's face, head, entirebody or exposed skin in place of the driver's eyes. For example, the ECUmay determine a current location of a face, head, entire body or exposedskin of a driver in block 608, may determine a location of the sunrelative to the face, head, entire body or exposed skin of the driver,determine an area of a window to shade to reduce an amount of sunlightreaching the face, head, entire body or exposed skin of the driver andthe like. In some embodiments, the user can select, using an inputdevice, the desired body part(s) to be shaded and in some embodimentsthis data is predetermined by the ECU. In some embodiments, the ECU candetermine the body part(s) to shade based on a location and time of yearof the vehicle. For example, if the vehicle is in Canada, shading of thedriver's skin may not be as important as if the vehicle is in a tropicalregion as the sun is weaker in Canada and may not pose as great a riskof causing skin cancer.

In some embodiments, the ECU may use machine learning to determine thelocation of the sun relative to the vehicle instead of, or in additionto, the steps shown in blocks 602 through 610. For example and withreference to FIG. 10, a method 1000 for determining a location of thesun relative to a vehicle using machine learning begins at block 1002.

In block 1002, the ECU may store previous locations of the sun relativeto the vehicle along with corresponding dates and times. This data maybe stored based on the detected locations of the sun relative to thevehicle and determined locations of the sun relative to the vehicle.

In block 1004, the ECU may analyze the stored locations of the sun andthe corresponding dates and times. Using this information, the ECU candetermine patterns corresponding to the locations of the sun at variousdates and times of day. For example, the ECU may learn that the locationof the sun shifts in a particular direction each day between January andJune for a particular location.

After sufficient data and analysis, the ECU will be able to determine alocation of the sun relative to the vehicle at a future date and time ofday. Thus, in block 1006, the ECU may determine a current location ofthe sun relative to the vehicle based on the detected data and analysisthereof.

Exemplary embodiments of the invention have been disclosed in anillustrative style. Accordingly, the terminology employed throughoutshould be read in a non-limiting manner. Although minor modifications tothe teachings herein will occur to those well versed in the art, itshall be understood that what is intended to be circumscribed within thescope of the patent warranted hereon are all such embodiments thatreasonably fall within the scope of the advancement to the art herebycontributed, and that that scope shall not be restricted, except inlight of the appended claims and their equivalents.

What is claimed is:
 1. A system for reducing sunlight shining into avehicle comprising: a window having an array of liquid crystals that caneach be switched between a transparent state and a shaded state in whichless light can pass therethrough; and an electronic control unit (ECU)coupled to the array of liquid crystals and configured to: determine acurrent location of a sun relative to the vehicle, select an area of thewindow to be shaded in order to reduce an amount of sunlight reaching aselected area of a cabin of the vehicle based on the current location ofthe sun relative to the vehicle, and control liquid crystals of thearray of liquid crystals within the selected area of the window toswitch from the transparent state to the shaded state.
 2. The system ofclaim 1, further comprising a sun location sensor configured to detectsun data corresponding to the current location of the sun relative tothe vehicle, wherein the ECU is configured to determine the currentlocation of the sun relative to the vehicle based on the detected sundata.
 3. The system of claim 2, further comprising a memory configuredto store the detected sun data including sun locations at specific daysand times of day, wherein the ECU is further configured to determinepatterns corresponding to the sun locations at the specific days and thetimes of day, and to use machine learning to determine the currentlocation of the sun relative to the vehicle based on the determinedpatterns.
 4. The system of claim 1, further comprising a memoryconfigured to store a sun location chart including multiple locations ofthe sun at multiple times of day for multiple days, wherein the ECU isfurther configured to determine the current location of the sun relativeto the vehicle by comparing a current day and time to the sun locationchart.
 5. The system of claim 1, further comprising a driver-facingcamera configured to detect a current location of at least a portion ofa driver, wherein the ECU is further configured to determine theselected area of the cabin based on the current location of the at leastthe portion of the driver.
 6. The system of claim 1, further comprisingan input device configured to receive user input corresponding to aselection of at least one of a desired size, a desired color, or adesired shape of shading of the window, wherein the ECU is furtherconfigured to control the liquid crystals in the selected area of thewindow to have the at least one of the desired size, the desired color,or the desired shape of the shading of the window based on the userinput.
 7. The system of claim 1, further comprising a driver facingcamera configured to detect image data corresponding to sunlight on adriver, wherein the ECU is further configured to move the selected areaof the window to a new selected area when the sunlight is on or neareyes of the driver based on the image data.
 8. The system of claim 1,further comprising an eye position sensor configured to detect alocation of eyes of a driver relative to the vehicle, wherein the ECU isconfigured to select the area of the window to be shaded to be betweenthe location of the sun relative to the vehicle and the location of theeyes of the driver relative to the vehicle.
 9. A system for reducingsunlight shining into a vehicle comprising: a window having an array ofliquid crystals that can each be switched between a transparent stateand a shaded state in which less light can pass therethrough; aninertial measurement unit (IMU) configured to detect a current headingof the vehicle; and an electronic control unit (ECU) coupled to thearray of liquid crystals and the IMU and configured to: determine acurrent location of a sun relative to the vehicle based on the currentheading of the vehicle, select an area of the window to be shaded inorder to reduce an amount of sunlight reaching a selected area of acabin of the vehicle based on the current location of the sun relativeto the vehicle, and control liquid crystals of the array of liquidcrystals within the selected area of the window to switch from thetransparent state to the shaded state.
 10. The system of claim 9,further comprising a memory configured to store a sun location chartthat associates a current time and day with a location of the sunrelative to earth, wherein the ECU is further configured to determinethe current location of the sun relative to the vehicle based on the sunlocation chart.
 11. The system of claim 9, further comprising adriver-facing camera configured to detect image data corresponding to acurrent location of a portion of a driver relative to the vehicle,wherein the ECU is further configured to select the area of the windowto be shaded based on the detected current location of the portion ofthe driver relative to the vehicle.
 12. The system of claim 11, whereinthe image data further corresponds to a location of sunlight relative toeyes of the driver, wherein the ECU is further configured to move theselected area of the window to a new selected area when the sunlight ison or near the eyes of the driver based on the image data.
 13. Thesystem of claim 9, further comprising a memory configured to store thedetected sun data including sun locations at various days and times ofday, wherein the ECU is further configured to determine patternscorresponding to the sun locations at the specific days and the times ofday, and to use machine learning to determine the current location ofthe sun relative to the vehicle based on the determined patterns. 14.The system of claim 9, further comprising an input device configured toreceive user input corresponding to a selection of at least one of adesired size, a desired color, or a desired shape of shading of thewindow, wherein the ECU is further configured to control the liquidcrystals in the selected area of the window to have the at least one ofthe desired size, the desired color, or the desired shape of the shadingof the window based on the user input.
 15. A method for reducingsunlight shining into a vehicle comprising: determining, by anelectronic control unit (ECU) of the vehicle, a current location of asun relative to the vehicle; determining, by the ECU, a cabin locationwithin a cabin of the vehicle to receive a reduced amount of sunlightbased on a location of a driver of the vehicle; selecting, by the ECU,an area of a window of the vehicle to be shaded in order to reduce anamount of sunlight that reaches the cabin location based on the currentlocation of the sun relative to the vehicle; and controlling, by theECU, liquid crystals within the area of the window to switch from atransparent state to a shaded state in which less light can passtherethrough than when the liquid crystals are in the transparent state.16. The method of claim 15, wherein determining the current location ofthe sun relative to the vehicle includes detecting, by a sun locationsensor, the current location of the sun relative to the vehicle.
 17. Themethod of claim 15, further comprising: storing, in a memory, a sunlocation chart that associates multiple days and times with multiplelocations of the sun relative to earth; and determining, by an inertialmeasurement unit, IMU data corresponding to a current heading of thevehicle, wherein determining the current location of the sun relative tothe vehicle is based on the IMU data and a comparison of a current timeand day to the sun location chart.
 18. The method of claim 15, furthercomprising: receiving, by an input device, user input corresponding to aselection of at least one of a desired size, a desired color, or adesired shape of shading of the window; and controlling, by the ECU, theliquid crystals in the area of the window to have the at least one ofthe desired size, the desired color, or the desired shape of the shadingof the window based on the user input.
 19. The method of claim 15,further comprising: detecting, by a driver facing camera, image datacorresponding to sunlight on the driver; and moving, by the ECU, thearea of the window to a new selected area when the sunlight is on ornear eyes of the driver based on the image data.
 20. The method of claim15, further comprising determining, by an eye position sensor, a currentlocation of eyes of the driver relative to the vehicle, wherein thecabin location is a location in the vehicle in which the eyes of thedriver are located.